Japanese Patent Laying-Open No. 2004-328991 discloses a drive apparatus for a vehicle. This drive apparatus drives one of front wheels or rear wheels as main drive wheels by an engine or an electric motor, and drives driven wheels by an electric motor that does not have a permanent magnet.
According to this drive apparatus, since the electric motor of the driven wheels does not have a permanent magnet, cogging torque is not generated and friction is small when the electric motor idles without generating a drive force. Therefore, fuel efficiency of the vehicle is improved.
The above-described publication, however, does not disclose a specific configuration for a case where the main drive wheels are driven by the electric motor. In the publication, a system configuration best suited for a motive power output apparatus including a motor with a permanent magnet and a motor without a permanent magnet is not proposed.